Really revert bench trigger changes.
BUG=skia:
NOTRY=true
R=kelvinly@google.com
TBR=kelvinly@google.com
Author: bensong@google.com
Review URL: https://codereview.chromium.org/324403009
diff --git a/bench/gen_bench_expectations.py b/bench/gen_bench_expectations.py
index a6f9605..6d44b6c 100644
--- a/bench/gen_bench_expectations.py
+++ b/bench/gen_bench_expectations.py
@@ -49,6 +49,7 @@
avg = sum(benches)/len(benches)
minimum = min(benches)
maximum = max(benches)
+ diff = maximum - minimum
return [minimum - diff*RANGE_RATIO_LOWER - avg*ERR_RATIO - ERR_LB,
maximum + diff*RANGE_RATIO_UPPER + avg*ERR_RATIO + ERR_UB]